Spacetime from a different perspective

[PakoThePlatypus]

I was thinking about spacetime today. Looking at the beginning of time (and space) we are not sure how it started. Some theorys suggest that the big bang happened from a single point called singularity, others that it happened everywhere at the same time. If it happened at a single point and is expanding, there needs to be an end of space (and time) in the form we know them today. So what happens if we reach that point? Can we just leave and come back like you would leave your house or do we enter another (kind of) world that existed before the big bang? If so, is the spacetime only some sort of a layer of a bigger structure or is it lying on some sort of infinite void? Also what laws of physics were present that an explosion like this could be created? Share your ideas and correct me if I'm wrong on any stuff above:) Also sorry for bad english

[Conscious Energy]

I do not think that you can have a different perspective on space(time) than Reality. 
 

As far as I understood it started from Nothing and it’s limit is our current common moment of Now or in other words Time ticks in every spot of space independent from the observers perception. 

[Phi for All]

2 hours ago, PakoThePlatypus said:

Share your ideas and correct me if I'm wrong on any stuff above:) 

2 hours ago, PakoThePlatypus said:

Some theorys suggest that the big bang happened from a single point called singularity, others that it happened everywhere at the same time. If it happened at a single point and is expanding, there needs to be an end of space (and time) in the form we know them today.

I will share some science, instead of my ideas. Based on the best current information, the universe isn't expanding INTO anything. The universe is all there is, so "from a single point" and "everywhere at the same time" are not different theories. The universe expanded from a very dense and very hot state, and the expansion evolved into what we observe now.

The LCDM model details all the maths that support this. Do you think there's a problem with the model?

2 hours ago, PakoThePlatypus said:

If so, is the spacetime only some sort of a layer of a bigger structure or is it lying on some sort of infinite void?

The universe may be infinite; we don't know. It may be finite, we don't know. The observable universe is finite.

Spacetime is geometry, not a physical thing that can be layered over a structure. You can't bring me a bucket of spacetime. It's a system of reference that denotes the degrees of freedom we have to move about; three spatial dimensions and a temporal dimension so we can measure when and where any phenomena take place. 

2 hours ago, PakoThePlatypus said:

Also what laws of physics were present that an explosion like this could be created?

NOT an explosion! Explosions explode outwards INTO something. The Big Bang was a rapid expansion of the whole universe. 

The maths we have can take us back until just a moment before the beginning of the expansion, but then they show us INFINTE densities and INFINITE heat, and we know that can't be right, so the model starts where our knowledge starts, at 10⁻⁴³ seconds after expansion began. We CAN'T know exactly what was going on before, since the last thing we know is that the entire universe was filled homogenously and isotropically (everything was made the same and behaved the same) with this density and heat. "Ideas" about what happened before can only be worthless guesswork, since there's no way to check or predict.

[Intoscience]

Just expanding on what Phi For All said. The current model only goes back to 10⁻⁴³ seconds after the expansion and it is hypothesised that spacetime may have begun at the big bang, therefore a "before" maybe a null concept, at least in terms of time. 

As to leaving the universe, well again this maybe a null concept, in that there is no "outside" of the universe. If the universe is larger than the observable universe then this  obviously implies an "outside" of the observable universe. In this case to go beyond the observable universe would require some fantasy way of travelling, wormhole or similar.  

It's very difficult, I suggest impossible, to conceptualise the universe and its origin. We are part of this universe and operate under its laws. Our experiences are bound within space & time, to even consider, with any worthwhile meaning, "outside" of these parameters is impossible.    

 

Edited July 21, 2021 by Intoscience